Greenhouse Gas Emissions

Desired Trend

Current Trend

Definition

Total carbon dioxide equivalent emissions per capita

Why is it Important?

Greenhouse gases (GHGs) are compounds that prevent heat from escaping the earth’s atmosphere, which causes the greenhouse effect and contributes to global climate change. Human activities that involve burning fossil fuels such as electricity production and transportation are the largest sources of man-made GHGs. Other man-made sources of GHGs include deforestation, industrial processes, and some agricultural practices. The primary types of GHG emissions are carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O).1 Each gas has a unique ability to trap heat, which is measured by its Global Warming Potential (GWP). Total GHG emissions are measured by converting each gas to carbon dioxide equivalents (CO2e) according to its GWP.

How are we Doing?

On average, residents in St. Louis County and the city of St. Louis emit 23.5 metric tons of CO2equivalents (MTCO­2e) per capita each year (based on data for 2008 and 2010).2 Greenhouse gas (GHG) emissions per capita in the St. Louis area are close to the average for the United States, which was 23.5 MTCO2e per capita in 2008 and 22.4 MTCO2e per capita in 2010.

Since 2005, the city of St. Louis has completed four inventories to track GHG emissions—in 2005, 2010, 2013, and most recently in 2015. According to its most recent inventory, over 7.2 million metric tons of carbon dioxide were emitted in the city in 2015. Commercial buildings were the biggest source of emissions, accounting for 42 percent of the city’s total. Residential buildings and emissions from vehicle travel each accounted for around one-fifth of the total (22 percent and 20 percent, respectfully). The emissions reported in the city’s inventories have declined since 2005. Between 2005 and 2015, GHG emissions decreased from 24.9 MTCO2e per capita to 22.9 MTCO2e per capita.

GHG emissions have also declined in the United States over the last decade, from 24.7 MTCO2e per capita in 2005 to 20.5 MTCO2e per capita in 2015. The United States is the source of around 15 percent of CO2 emissions globally3 but home to less than 5 percent of the world’s population.4 According to the U.S. Environmental Protection Agency, over 90 percent of U.S. CO2 emissions come from fossil fuel combustion. The biggest fossil fuel contributors include emissions from electricity generation (35 percent of total CO2 emissions in 2015) and transportation emissions (32 percent of total CO2 emissions in 2015).1

Geographic Level

St. Louis County and the city of St. Louis (data for additional areas within the eight county region will be added if it becomes available)